It’s a question probably someone asks every day, probably. On the face of it, it would seem as simple as asking which way is up. I mean, what is the fastest car in the world? There must be an answer. Just line them up and race them, or something, right? What’s there to complicate the matter?

Not so fast, though. It turns out that in the high stakes prestige affair of crowning a car as the fastest, there may in fact be somewhat more considerations than you’d think. And “considered” such matters would appear to need to be. Indeed, dispute about the very the definition of what is a “car” led to some considerable controversy in 2013 regarding which car did or did not qualify to wear the crown.

Before we dive right into that matter, we should first introduce the players in this little drama of ours. Three cars are especially important to this story. The first of these is the Bugatti Veynon Super Sport: the reigning king. You might call it the European Union of sports cars, produced by a Franco-German collaboration. Owned by Volkswagen, the car is assembled in the small French town of Molsheim. The Bugatti accelerates from 0 to 60 mph in 2.4 seconds, driven by an 8.0 liter W16 engine that works up 1,200 bhp. The Guinness Book of Records has certified it as reaching the track speed of 267.8 mph.

Bugatti’s competition is, on the one hand, the Hennessey Venom GT. This car hits a speed of 265.7 mph under the drive of its 7.0 liter V8 twin turbo engine producing 1,244 bhp. Its acceleration speed of 0 to 186 mph in 13.63 seconds has been certified. On the other hand, we have the SSC Ultimate Aero. This car has been crowned the world’s fastest on two separate occasions. In 2007 it recorded a certified speed of 256.18 mph, earning its first title, which it kept for almost three years. However, its second crowning proved to be rather controversial. Before turning to the controversy, though, in addition to identifying the players, we should know the rules of the race.

To be clear, here, any claims about a car being the fastest in the world are really about whether it is the fastest “production” car. Production car, you ask? The only cars that qualify under this rule are ones that can be bought commercially. Vehicles, that could perhaps be called cars (even if they more resemble rockets), but are only legal to drive places like the Utah salt flats, don’t count. Only a car that can be legally purchased and driven on city streets counts as a production car.

Only such cars qualify for the race, as it were. Those that have been modified from their retail form, so as to amplify their race track speed obviously are disqualified. Who would quibble with that, if the point is to speed test actual production cars? That would seem like a pretty straightforward matter. Well, as it happens, not really so straight forward after all.

In 2010 Bugatti took the crown of world’s fastest car away from the SSC Ultimate Aero. The German-French collaborative car reigned uninterrupted, until April of 2013. At the very beginning of that month, John Hennessey, car guru of the Hennessey Venom GT, alleged having set the production car record by hitting 265.7 mph. As this was not a certified test it posed no threat to the Bugatti record. And, anyway, Bugatti’s record was faster than that, at 267.8 mph. Rather, what led to the controversy was that Hennessey also noted in passing that, in fact his car’s speed really did make it the actual fastest production car in the world. And the reason he cited was that Bugatti attached a speed limiter to their retail cars.

So it turned out to be. In fact, Bugatti Venyon Super Sports bought commercially had a safety system installed that prevented the car from exceeding 258 mph: a speed 10 mph below the track record of the car. When this situation came to the attention of the Guinness Book of Records a great storm of controversy soon followed. The Guinness adjudicators concluded that this was the kind of modification for speed testing purposes that the rules disqualified. The Bugatti, in their new estimation wasn’t in fact a production car. Its crown was duly revoked. The Hennessey’s speed though had not been officially certified, so the crown for fastest car in the world reverted back to the prior record holder, the SSC Ultimate Aero.

A strange situation this one surely was: the point of a rule against modified cars was, one would understand, to disqualify cars not sold commercially. For instance, cars taken off a commercial production line, and modified specifically for racing purposes where intended to be excluded. The present situation, though, was a little more difficult to align with the rules. The Bugatti, after all, wasn’t modified for advantage on the track, but for safety on the street. This was certainly a modification that made the car faster on the track than on the street, yet the production car hadn’t been modified to be faster, but rather to be slower. Clearly this was an unusual situation; how exactly was the rule to be applied?

Auto aficionados remain somewhat divided about the correct interpretation of the rule: whether the limiter-less car being allowed to compete constituted a rule violation. The Guinness officials though decided that such a ruling would contravene the spirit of the rule. Just a few days later they took a sharp U-turn and reinstated Bugatti as reigning king of the world’s fastest cars.

Whichever way you cut it, though, it seems a bit odd calling such cars production cars. They are assembled from a variety of system sources, hand assembled in craftsman-like processes and result in a very small handful of the cars only ever being on the market. All this just goes to show that the definition of “production car” may very well just be in the eye of the beholder. But who can deny that rules are made to be broken?

To read more by Samson Altrus, on the unique production qualities of the Bugatti, click here